Young Eup Jin

Organic Synthesis and Characteristics of Novel Conjugated Polymers with Cyano Group and Carbazole Unit for AMOLEDs

The present investigation deals with the synthesis, characterization and EL of new copolymers, CzCNPFV1, CzCNPFV2 and CzCNPFV3 by Knoevenagel condensation reaction. The CzCNPFVs was synthesized for promoted efficiency of reported CNPFV. The PL emission spectra of the CzCNPFVs in chloroform solution show maximum peaks at 476 ~ 479 nm. In thin films, maximum peaks of the CzCNPFVs appeared at 501 ~ 504 nm, red-shifted around 25 nm as compared to that in solution. The more negative energy of the LUMO of CzCNPFV1 or CzCNPFV2 indicates the electron injection process is easier than in CNPFV. From this result, higher quantum efficiency of CzCNPFV1 or CzCNPFV2 as compared to that of CNPFV can be expected due to its improved electron injection ability from the cathode.

Coating properties of UV-curable polyurethane acrylate composites with lotus leaf powder

ABSTRACT Eco-friendly water-repellent UV-curable polyurethane acrylates (PUA) with fluorine groups were synthesized from H12MDI which is excellent yellowing resistance and water resistance, polycarbonate diol, perfluoropolyether (PFPE) diol, and 2-hydroxyethyl acrylate. As increasing to 10% PFPE in polyol content, the contact angle of the cured PUA increased from 75.9∘ to 107.1∘ while tensile strength decreased and elongation increased due to the flexibility of PFPE. To improve their hydrophobicity, composites were prepared by adding small amounts of lotus leaf powder (LLP). The obtained PUA/LLP composite with 2% LLP showed much hydrophobicity, 120.6∘ of contact angle but their mechanical properties were not affected by adding LLP.